Procoagulant activities of plasma factor VIIc and factor Xc are positively and independently associated with concentrations of the high-density lipoprotein apolipoprotein, apo A-II
Maria Atta1, David Crook2, Faria Shafique1, Desmond G. Johnston1, Ian F. Godsland
1Endocrinology and Metabolic Medicine, Imperial College London, London, UK; 2Clinical Investigations and Research Unit, Royal Sussex County Hospital, Sussex, UK
Summary
The pro- and antiatherogenic roles of apolipoproteins B and A-I, respectively, are well-established although the importance of apolipoprotein A-II remains unclear.There is extensive evidence for the involvement of plasma lipoproteins in haemostatic function. However, in-vivo studies of relationships between haemostatic variables and apolipoprotein concentrations are very limited. Plasma fibrinogen, factorsVIIc and Xc (FVIIc and FXc, respectively), apolipoproteins (apo) A-I, A-II and B, triglycerides, total, low-density and high-density lipoprotein (HDL) cholesterol, and cholesterol in HDL subfractions 2 and 3 were measured in 186 apparently healthy Caucasian men (aged 26–78 years; body mass index 19.9–37.8 kg/m2). Associations between haemostatic, apolipoprotein,lipid and lipoprotein variables were explored in uni- and multivariable analyses. Fibrinogen did not correlate with any of the lipid-related variables. FVIIc and FXc were significant positive univariate correlates of total cholesterol (correlation coefficients 0.26,p<0.001 and 0.19,p<0.05,respectively) triglycerides (0.37, p<0.001 and 0.36, p<0.001), and apoB (0.21, p<0.01 and 0.17, p<0.05) and apoA-II (0.19, p<0.05 and 0.29, p<0.001). HDL2 subfraction cholesterol correlated negatively with FVIIc and FXc (-0.20, p<0.01 and –0.22, p<0.01, respectively). In multivariable analysis, only the associations of FVIIc and FXc with total cholesterol, triglycerides and apoA-II remained statistically significant. In conclusion, total cholesterol and triglycerides were the major independent lipid correlates of FVIIc and FXc. The independent and positive associations of apoA-II with FVIIc and FXc suggest a prothrombotic involvement for this apolipoprotein. Keywords
fibrinogen, factor X, lipids, Factor VII, Apolipoproteins, high density lipoprotein, apoA-II
DOI
http://dx.doi.org/10.1160/TH08-04-0213